True Probability
Definition
True probability is the estimated real likelihood of an outcome occurring, stripped of any bookmaker margin. It is derived from sharp market lines or statistical models and serves as the benchmark against which you measure value.
Formula
True Prob = Implied Prob of each outcome / Sum of all Implied Probs (vig-removed)Example
A two-way market prices outcomes at 1.87 and 2.05. Implied probs are 53.5% and 48.8% (total 102.3%). Removing vig: true probs become 52.3% and 47.7%.
Related Terms
Closing Line Value (CLV)
AnalyticsClosing Line Value measures the difference between the odds at which you placed a bet and the final odds when the market closes. Consistently beating the closing line is widely regarded as the single best predictor of long-term profitability because closing odds reflect the most efficient market price after all information has been incorporated.
Expected Value (EV)
AnalyticsExpected Value is the average amount you can expect to win or lose per bet if the same wager were repeated many times. A positive EV (+EV) bet is one where the bookmaker's odds imply a lower probability than your estimated true probability, giving you a mathematical edge.
Implied Probability
AnalyticsImplied probability is the conversion of betting odds into a percentage that reflects how likely the bookmaker considers an outcome. It includes the bookmaker's margin (vig), so the sum of all implied probabilities in a market exceeds 100%.
Market Efficiency
AnalyticsMarket efficiency describes how accurately betting odds reflect the true probabilities of outcomes. Highly efficient markets (e.g., NFL totals at Pinnacle close) leave very little edge, while less efficient markets (minor leagues, props) may offer exploitable discrepancies.
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